Railway traffic controlling apparatus



April 32- H. v. RUDOLPH ET AL 1,855,611

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WATTORNEY Patented Apr. 26, 1932 warren STATES PATENT OFFICE.

HAROLD V. RUDOLPH, OF VIILKINSBURG, AND HAROLD W. BRYAN, OF SOUTH HILLS,

PENNSYLVANIA, ASSIGNORS TO UNION SW'ITGH & SIGNAL COMPANY, OF SWISS- .VALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA A RAILWAY TRAFFIC CONTROLLING APPARATUS Application filed November 26, 1930. Serial No. 498,358.

Our invention relates to railway traffic controlling apparatus, and particularly to automatic train control systems of the intermittent inductive and continuous inductive types. More particularly, our invention relates to the train-carried portion of such systems.

One object of our invention is to provide traincarried apparatus whichmay be used in an intermittent inductive train control system or with a continuous inductive train control system in such manner that the same brake applying apparatus may be utilized for both systems.

Another object of our invention is to provide train-carried apparatus in which the same acknowledgin and resetting devices may be used for both systems.

Other objects of our invention will appear as the description proceeds.

e will describe two forms of railway traffic controlling apparatus embodying our invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a view, partly diagrammatic and partly crosssectioned, illustrating one form of railway traffic controlling apparatus embodying our invention. Fig. 2 is a similar view showing a modified form of the apparatus illustrated in Fig. 1, and also embodying our invention.

Similar reference characters refer to similar parts in both views.

Referring first to Fig. 1, the reference characters 1 and 1 designate the track rails of a stretch of railway track over which traftic normally moves in the direction indicated by the arrow. These track rails are divided, by means of insulated joints 2 into a plurality of track sections, only three of which D-E, EF and FG, are illustrated in the drawing. Each track section is provided with the usual track circuit comprising a suitable source of current, here shown as a track battery 3, connected across the rails adjacent the exit end of the section, and a track relay, des ignated by the reference character T with an exponent corresponding to the'locatiom-connected across the rails adjacent the entrance end of the section.

The rails of section DE are also supplied with alternating train. controlling current under the control of traflic conditions in advance of the section. As here shown, this latter current is furnished. by interposing between the track battery?) and one rail 1 of the section, the secondary f a transformer H, the primary5 of which is at,- times supplied with alternating train controlling current from the secondary 7 of a transformer J. Thelprimary .8 of transformer J is constantly connected with asource ofalternating current which is not shown inthe drawin The circuit for primaryv 5 of transformeiii includes a. front contact 6 of track-relay T and it will be apparent, therefore, that alternating train controlling current is supplied to the rails of section DE when section EF is unoccupied but not when thissection is occupied.

Located adjacent the entrance end of section F-G is a trackway-inductor K of the usual form having a magnetizable core 9 provided with a winding 10. As hereshown, the circuit for winding 10 is controlled by'a front contact 11 of track relay T so that this winding will be short-circuited when section FG is unoccupied and open-circuited when this section is occupied;

As shown in the drawing, section'DE is occupied by a train W. Located in advance of the forward axle of this train is a receiver L of the usual form commonly employed in train control systems of the continuous inductive type, and comprising two magnetizable cores'12 and 12 disposedin inductive relation with the track rails 1 and 1", respectively, and provided with windings 13 and 13 The windings l3 and 13'? are included in a receiving circuit at, these windings being connected in series in this circuit in such manner that the potentials created in these windings by alternating current flowing in opposite directions in the two track rails are additive.

The currents thus induced in the receiving circuit a are utilized to control the supply of current to the two stator windings 15 and 16 of aninduction motor relay-N, suitable amplifying and phase splittingapparatus M being interposed between the receiving circuit and the relay windings. The amplifying and phase splitting apparatus M may have any suitable form and may, for example, be similar tothat shown and described in Letters Patent of the United States, No. 1,566,331, granted on Dec. 22nd, 1925.,toL. V. Lewis, for Railway traflic controlling apparatus. A condenser22 'is connected across the winding '15 ofrelayNin'theusualmanner to tune the circuit *inludingthiswinding to resonance at thefrequency ofthe-train controlling current supplied to the rails, and a condenser 23 is likewise connected across r the Winding 16 for a similar purpose.

' Relay TN also comprises 5a rotor 17 which contro'ls i-four contact fingers 18, =19, 20 and 21, these fingers 'being normally ibiased to occupy vertical-or neutral positions when the relay .is :deenergized. The amplifier and phase splitter TM "isso constructed, and the parts are so arranged that, :under normal 'c'onditi'onsfwhen current is being supplied to the reeeiving circuita by the :receiver EL,

:the windings and 16- will beisuppliedwith currents of such'sa magnitude :and instantaneous :polarity that the contact Ifinger-s 1-8, 19, and Ql'will be swung toward the might, thereby closing -the :normal :contacts of 'the delay. I

' 'The traimcanried apparatus further 'includes an acknowledgin'g switch 'AFand a reset 'switch R which, Itogether with the relay .N, control an acknowledging =relay P having slow release characteristics. Asfthere shown, the acknowledgingswitch Acomprisesa normally closed contact '30f3.'1, sand :three nor-- *ma'lly open con'tacts 30?32, :and 3T) 36. #Similarly, the :reset switch comprises aFHOI III-ZIHYQlOSGd contact ?37-38,:and

three normally I open contacts -37-39 i40'41 und d-M3. The'rese'tsswitch iR-avill usually 'be located insuchsapositioinon ithetrain that n it is inaccessible to the engineman while the train is in motion. 1

lt-clay P is provided with an acknowledging circuit whichzpasses from-terminal iB-of -a suitable source 'oficurrent rnot: shown -in :the drawings through wire '45, normally :closed contact 44 i of 'a pneumatic relay Y, wire 46, norinally open contact 35 36 GfFSSQlZrSW-lbflh A, wires a'l and 4:8, iwinding of :relay :P, wires '49 :and T50, :neutral contact 19-;26 :of :relay N, and Wire 5531 :to the other terminal LC of the source. Relay 2]? is also provided with :a reset :circuit which passes :firom zterminal B through wires $52 :and :53,inorma1ly open -contact42'48 o'f=reset switch R, .wires 47 and 48, win'ding of relay 21?, wires 49 and:50, neutral contact 1926 of relay'EN, and-wire 551 to itermina'l C. Relay 5P z-is :furtherprow ided=with a stick circuit whichzpasses from terminal 13 through neutral contact 20%27 ofrelayN, wires 64'and -89, firont contact-I90 df"-1"el ay -'P,'-wires 91- and 48, winding of relay P, wires 49 and 50, neutral contact 1926 of relay N, and wire 51 to terminal C.

The relay N and the relay P ointly control a brake controlling magnet valve Q} comprising a=valve stemrol biasedi-to-an upper position by a spring 55, and provided with a winding 56 and an armature 57. The magnet valve Q controls the brakes in such mannerthat an automatichmke application occurs at the expiration 'of a 'given interval 'ortime i o-llowingthe deenergization of mag- .net .valve .Qfi. Themagnet valve Q} also controls an'indicating device here shown as a whistle .S, a. check valve U being interposed between the whistle and the valve for reasons .vhi'ch. will be :made clear as the description proceeds.

.Magnet valve 2& provided with a .circuit, which is closedfwhen relay ,N :is energized in the normal direction :and -;relay P is deenergized, .and which :passes :from iterzmin'al 13 through nvire 5.9, normal contact '18--2lofrelay .N,:wires and94,,;baclecontact-95.96 of celery P, wire-197, winding 56 of :magnet valve 1Q}, wire -98, back contact 9.910O of relay -P, wires 101 and=63, and normal contact ;21-:2:8- ofrelay N 'toterminal C. Magnet valve Q is also provided 'wit'lLa circuit which :is closed when ,relay -'P .is enecrgized, ;and which :passes =from terminal 13 '1 through wires 59 :and F109, front contact 95-103 of relay 1?, wire .97, winding 556-01. :magnet valve -Q, wire 98, front contact 99104: of relay 1 =.and wires 105 and 51 back {t0 terminal- C.

'The relay N iinndditiontocontrolling the unagnet valve Q andithe relay P, also acontrols two indicating devices here 1-Sl1QW1i as :electric' lamps V and V which, when illuminated, indicate gproceed andstop, respecztively. Lamp V is provided with a'circuit which passes from terminal B through :vcire 59,';nor1nal contact l8-2l of relay N, wires 60 and 611, the {filament of lamp 3 wires 62 and-.63,.and:normalcontact 21 28 of relay N back to terminal C. Lanip V is provided with 'acircuit which ,passes from terminal B through 'neutral'contact 20e27 of relay N,'.w.ires 64=and-67., the filament of damp V Wires66 and .50, neutral contact 19-26 of relay N, and wire 51 back to battery C. :Lamp v isalso provided .withacircuit .which passes from terminal B through wire :59, reverse :contact 1,8.25 of relay N, :wires 92,-64-and67dthe filament-of lamp V wires :66, -50 and ,93, :and vcontact 2l129 of relay -N., back to battery C.

"The train-carried apparatus thus far described corresponds to ,that commonly em- ;ployed in traincontrol systems of-the continnous rinductivetype. In addition, the traincarried apparatusincludesa second receiver V= of the :usual :form :commonly employed in :train control systems o'f'the intermittent inductive type, and comprising-acnagneti-zable 7 core 68 provided with a primary winding 10 and a secondary s. The recerverV 1s located as to register with the trackway inductor K previously described in the usual and well known manner. 7

The train-carried apparatus further includes a relay X of the usual type commonly employed in intermittent inductive train control systems, and a second brake controlling magnet valve Q which is exactly like the valve Q}, and which is also arranged to initiate an automatic application of the brakes at the expiration of a given interval of time following the deenergization of this latter magnet valve.

As shown in Fig. 1, when magnet valve Q is energized, it connects a timing reservoir 73 with a pipe 71 which, in turn, is connected with a pipe 72 through the valve Q when valve Q is energized. The pipe 72 is constantly connected with a suitable source of fluid pressure not shown in the drawing. The reservoir 73 is connected with a relay valve Z, so that when this reservoir is charged, the valve is depressed, and a pipe 75, which is connected to apparatus (not shown) for causing an automatic application of the brakes when this pipe is opened to atmosphere, is then disconnected from atmosphere. Pipe 75 is also connected with the pneumatic relay Y referred to hereinbefore by means of a pipe 74:, and when the pipe 7 5 is disconnected from atmosphere, contact 44: is closed as shown in the drawing. If'magnet valve Q becomes leenergized when magnet valve Q} is energized, timing reservoir 73 will be opened to atmosphere through a restricted orifice 76 in valve Q and also-through a check valve U and the whistle 'S, which under these conditions gives an audible indication to the engineman that the timing reservoir is being exhausted. It will be noted that when the whistle S is connected with the reservoir 7 3 in this manner, the check valve U prevents the escape of fluid through the restricted orifice 77 in valve Q}. After an interval of time, such as six seconds, valve Z will reverse, thereby venting pipe '75 to atmosphere, and this wiil cause anrautomatic application of the brakes, and will also cause contact e't of pneumatic relay Y to open If valve Q} becomes deenergized when valve Q is energized, reservoir 7 3 will then be connected with atmosphere through valve, Q pipe 71, valve Q and restricted orifice 77, as

well as through valve Q pipe 71, valve Q check valve U and whistle S. Under these conditions, after an interval of say six sec-.

3031 of the acknowledging switch A, wire T 78, normally closed contact 3738 of the reset switch R, wire 79, winding 56 of magnet valve Q wire 80, normal contact 81-82 of relay X, wire 84, and primary winding 10 to terminal C. The normal circuit for the secondary winding 8 is from terminal B through wire 52, normally closed contact 30-81 of acknowledging switch A, wire 78, normally closed contact 8738 of reset switch B, wire 79, winding 56 of magnet valve Q wire 80, normal contact 828182 of relay X,-wire 85, winding of relay X, wire 86, secondary winding 8 to an intermediate point in the primary winding 79, and then throughthe right hand portionof this winding to'terminal C. A spark arresting device 87, here shown as a rectifier, is connected across primary winding 29, and a similardevice 88 is connected across the winding 56 of magnet valve Q The operation of the entire apparatus is as follows: As shown in the drawings, section E-F is unoccupied, and train'controlling current is therefore supplied .to they track rails 1 and 1 of section D E, so that relay N is energized in its normal direction. The circuit for lamp V is therefore closed, and this lamp is lighted, thus giving a visible indication to the engineman that trafiic conditions in advance are safe. Acknowledging relay P is deenergized, and the circuit previously traced for magnet valve Q} is therefore closed at back contacts -96 and 99-400 of relay P, and at normal contacts 1'8-24- and 21--28 of relay N. 'Magnet valve Q} is therefore energized, so that pipe 71 is connected with the source of fluid pressure. Belay X is energized by virtue of the normal circuit previously traced for the secondary s of receiver V which is closed at contact 8281-83 of relay X, and since magnet valve ,f is included in this circuit this magnetvalve is likewise energized. timing reservoir 7 3 is therefore charged with fluid-pressure, and the relay valve Z occupies its lower position in which pipe 75 is blanked. Contact 44; ofpneumatic relay Y is closed. It follows that as long as section D-E in advance of thetrain TV, and section EF are unoccupied, the train V may proceed through the remainder of section DE without incurring an automatic application of the brakes.

We will now assume that the supply of train controlling current to the receiver L is cut off due, for example, either to the presence ofa train in section D-E in advance of the-train W, or to a train in section EF which causes track relay T to become deenergized. Under these conditions, relay N becomes deenergized, thereby opening its normal contacts 1824 and 2128, and closing its neutral contacts 19-26 and 29-27.

The opening of normal contacts 1824E and 2128 of relay N interrupts both the circuit for lamp V and the circuit for magnet valve Q}. The lamp V therefore becomes extinguished, and the valve O} becomes deenergized. The closing of neutral contacts 19 26 and 2027 of relay N completes the circuit previously traced for the lamp V and this lamp becomes lighted to indicate that traflic conditions in advance are dangerous. The deenergization of magnet valve Q} will, after the predetermined time interval. result in an automatic application of the brakes unless the cngineman is alert and reverses the acknowledging switch A before the expiration of the time interval. Assuming he does this, the acknowledging circuit previously traced for acknowledging relay P will then be closed at normally open contact 35-36 of acknowledging switch 1%., and acknowledging relay P will therefore become-energized. When relay P is energized, the circuit previously traced for magnet valve Q is closed at front contacts 95--103 and 99-104 of relay P, and magnet valve Q again becomes energized, so that reservoir 73 is again connected with the source of fluid premure. Furthermore, when relay P becomes energized, it closes its stick circuit at its front contact 90. It follows that after the acknowledging switch has been operated under these conditions, it may immediately be returned to its normal position, and relay P will remain energized, so'that valve Q}, after being reenergized, will subsequently remain energized, and prevent an automatic application of the brakes. The parts will then remain in these latter conditions until train controlling current is again supplied to the receiver L, at which time relay N will again become energized and close its normal contacts, thereby deenergizing relay P, and restoriu the parts to the conditions in which they are illustrated in the drawings.

, e will now assume that the engineman was not alert and did not reverse the acknowledging switch A prior to the-automatic application of the brakes due to the supply of train controlling current to the receiver L being cut off. The brake application will result in normally closed contact 44 of pneumatic relay Y being opened, so that relay P cannot be energized by closing the acknowledging switch A. The engineman must therefore reverse the reset switch R, which cannot be done until the train has come to a full stop. When reset switch R is reversed, the reset circuit for acknowledging relay P becomes closed at normally open contact 4243 of reset switch R, and relay P therefore becomes energized and completes its stick circuit. Magnet valve Q then again becomes energized, and the brakes can be released. Relay P will now remain energized until train controlling current is again supplied toreceiver L to energize relay N in its normal direction, at hich time relay P will become deenergized and lamp V will become lighted. The parts will then be restored to the conditions in which they are illustrated in the drawings.

It should. be pointed out that if relay N becomes energized in the reverse direction for any reason so that its contacts are swung to the left, the circuit for lamp V including reverse contacts l825 and 21 29 of relay N will become closed, and this lamp will become lighted thereby giving a stop indication on the train. Furthermore, all circuits for valve Q} will then be open, so that valve Q will become deenergized. If the engineman operates the acknowledging switch A under these conditions before an automatic application of the brakes occurs, relay P will become energized by virtue of a branch for the acknowledging circuit previously traced for this relay, which branch passes from wire through wire 93, and reverse contact 2129 of relay N to terminal 0. l/Vhen relay P becomes energized, it completes a stick circuit which passes from terminal B through wire 59, reverse contact 1825 of relay l wires 92, 64; and 89, front contact 90 of relay P, wires 91 and 48, winding of relay P, wires l9, 50 and 93, and reverse contact 2129 of re lay N to terminal C. Relay P will therefore remain energized even though acknowledging switch A is immediately returned to its normal position, and it will be apparent, therefore, that valve Q will again become energized and prevent an automatic application of the brakes so that the train can proceed. If lamp V continues to be lighted for any considerable length of time, however, the engineman will then know that the apparatus is not functioning in the normal manner.

If the engineman does not operate 5 itch A under the conditions just stated before an automatic application of the brakes occurs, he will have to operate reset switch R. If he does this, relay P will then become energized by virtue of a branch for the acknowledging circuit which is the same as the branch just traced for the reset circuit. If relay P is energized in this manner, it will then re- 'main en'ergized until relay N is again energized in its normal direction. This arrange ment insures that improper operation of the apparatus will be detected.

WVhen the train passes out of continuous control territory, as is the case when the train leaves section D-E, the supply of current to the receiver L will of course be cut off,

and unless the engineman demonstrates his cognizance of the fact that he is leaving continuous territory by reversing the acknowledging switch A, an automatic application of the brakes will occur in the manner previously described. He will then have to wait until the train has come to a standstill and operate the reset switch It before the train can again proceed. When the acknowledg ing switch A is reversed under the above conditions, or the reset switch R is operated, relay P will become energized and will subsequently remain energized by virtue of its stick circuit previously traced, until the re ceiver L is again supplied with train controlling current due to the train having again entered continuous control territory. As long as the train is out of continuous control territory, relay N will he deenergized and lamp V will be lighted.

We will now assume that with relay P held in its energized condition by virtue of its stick circuit, and with the rest of the traincarried apparatus in the condition shown in the drawings, the train passes an inductor K, having its winding 10 open-circuited. Under these conditions, while the train is pass-- ing the inductor K, the reluctance of the magnetic circuit for the receiver V will be considerably reduced, and so the flux traversing the receiver core 68 will rapidly increase as the receiver approaches the inductor, and will decrease as the receiver recedes from the inductor. This will produce a complete cycle of two alternations of electromotive force in the secondary winding 8, and the voltage of one of these alternations will neutralize or reverse the current through the winding of relay X, thereby causing the latter relay to open its contacts. This will deenergize the primary winding 39 and the magnet valve Q and will, of course, open the stick circuit for relay X. The deenergization of magnet valve Q will, after the predetermined time interval, result in an automatic application of the brakes in the manner previously described.

If the train passes the-inductor K when its winding 10 is short-circuited, themagnetic action will be the same as before, except that the voltage induced in the receiver secondary s will be very much lower and will not be sufiicient to deenergize relay It follows that an automatic application of the brakes will not occur.

lVe will now assume that the circuit for the trackway inductor winding .10 is open, that the train-carried receiver V passes over the inductor, and that the engineman reverses the acknowledging switch A Just before the receiver registers with the inductor.

An acknowledging circuit will then be closed, which circuit passes from terminal.

Bthrough wire 45, normallyclosed contact 44 of pneumatic relay Y, wire 46, normally. open contact 33-34 of acknowledging switch A, resistance element 70, wire 85, winding of relay X, wire 86,. secondary winding 8, and the. right hand portion of primary winding 29 to terminal C. i

A branch circuit is also closed, which circuit passes from'terminal B through wire 52, normally open contact 30 32 of acknowledging switch A, wires 118 and 119, substitute resistor-element 69, wire 84, primary winding p to terminal C.

It follows that under the condition specie I fied, the relay X will remain energized, so that if the engineman returnsthe acknowl edging switch to its normal position before an automatic brake application occurs due to s the deenergization of magnet valve Q}, the brake application will be forestalled and the train may proceed. The purpose of the sub-- stitute resistance element 69 is to provide the acknowledging circuit just traced with the equivalent of the winding 56 of the magnet valve Q thereby avoiding any disturbance in the circuits for the primary and secondary windings of the receiver V due to the fact that the winding 56 of the magnet valve Q is taken out of the circuits for the primary and secondary windings during the acknowledging process.

JV-e will now assumethat the engineman does not reverse theacknowledging switch A prior to an automatic application of the brakes due to coaction of the receiver V with an open-circuited inductor K. Thebrake application will result in normally-closed contact 44 of pneumatic relay Y being opened so that relay X cannot again be energized by operation of the acknowledging switch A. When the train has come to a full stop, the engineman will reverse the reset switch R, thereby closing the following circuit: From.

terminal B through wires 52 and 53, normally open contact 4041 of reset switch A, resistance element 7 0, wire 85, winding of relay X, wire 86, secondary windings, and the right-hand portion of primary winding [9 to terminal C. This willenergize relay X, so that when the reset switch R is restored to its normal position, the magnet valve Q, will again become energized and the brakes can be released. The parts will then be re-- stored to the conditions in which they were. before 7 the automatic application of the brakes occurred with the result that the train may proceed. a

It will be noted that'when the acknowledgingswitch A is reversed, the circuit for the. magnet valve Q becomes opened,so that if this switch is reversed and left in the reverse position for more than the time required. for the brake applying app aratus to function, an automatic application ofthe brakes will occur. switch R. It follows that neither oneof these switches can be tied or otherwise heldin the The same thing is true of the reset the " described.

. connect a whistle S with the pipe 71.

reverse position to defeat'the'object of the system. p

One advantage of the apparatus shown in Fig. 1 is that the same brake applying apparatusis utilized for both systems with the result that the amount of brake applying equipment required for'the combined system is reduced to. a minimum.' Another advantage of the'apparatus shown in Fig. 1 is that same resetting and acknowledging switches are'utilized 'for'both systems. This likewise results in a reduction of the number of parts re uired when it is desired to equip a train wit a combined system of the type the apparatus is similar to that shown in Fig. 1. I v I A The operation of the apparatus shown in Fig. 2-is'; substantially the same as that shown in Fig. l'with the exception that when valve Q becomes deenergized, it does not initiate an automatic application of the brakes, but merely; causeswhistle S to blow. After whistle S has started'to blow, it will continueto blow'until the 'engineman' operates the acknowledging switchA to energize acknowledging relay? and hence reenergize valve Q In conclusiomit should be pointedout that we have provided train-carried apparatus comprising a minimum number of parts for cooperating either withtrackway circuit provided in continuous train control territory such as illustratedin connection with section D'E',- or with traclzway inductors similar to inductor K, which are located at intervalsalonga stretch of intermittent control territory; By' this arrangement, a train provided with apparatus embodying our invention may be operatedover either continuous or intermittent territorywith full protection and without manual interference with'or adjustment of the train-carried apparatus.

Although;wehave herein shown and describedon-ly two forms of railway trafiic controlling apparatus embodying our invention, it is understood that various changes and modifications may bemade therein-within the scope of the appended. claims without departingfrom the spirit andscope' of our invention.

Having thus described our'invention, what we claim is 1. Railway trafiic controlling apparatus comprising two normally energized traincarried windings, means on the train cooperating with devices located at intervals along the trackwayfor at times deenergizing one of said" wmdlngs, means onthe train controlledby currents in the-track-way' for at other times deenergizing the other winding, single means controlled by both said windings for initiating an automatic applicationof the brakes on the train when'either of said magnets has been deenergized for a glven 1nterval of time; and single manually operable means on thetrai'n effective during said interval of time'for reenergiz'ing the deenergized winding to preventan automatic application' ofth'e brakes:

2. Railway traflic controllingapparatus comprising two normally energized traincarried windings, means on thetrain cooperating with devices located at intervals" along the traclrway forat times deenergizing one of said windings, means on the tram controlledby currents inthe tra'ckway for at other times deenergizin-gthe other winding, single means'conti'olled'by both said wind ings for initiating an automatic application of the brakes on the train when either of'said magnets has been 'deenergized for a given interval'of time, a normally closed contact on the train,- means for opening said contact upon an automatic application of the brakes, and single "manually operable means includ ing said contact for reenerg'izing either winding after such winding hasbecome' deenergized.

3. Railway traffic controlling apparatus comprising two normally energized train carried windings; means onthe train cooperating with devices located atintervals along the track way for at times deenergizing-"one of said windings, means on the train controlled by currentsin'the 'trackway' for at other times deenergizingthe other winding, single means-controlledby both said windings: 'for initiating an automatic application ofthebrakeson-thetrain when either of said windings has been" deenergized'for a given interval of time," a-normally closed contact on a the train, means for opening said contact upon an automatic application of the brakes, an acknowledging switch on the train, and

means on the train controlled by said acknowled'ging switch' and by said contact for reenergizing either winding'after such winding. has become deenergized.

4. Railway traiiic controlling apparatus comprising. two normally energized traincarried windings,- means on the train cooperating' with deviceslocated at intervals along the trackway: for attimes deenergizing one of 'said' windings, means onthe train controlled by-currents in the trackwayfor at other times deenergizing the other winding, single means controlled by both said windings for initiating an automatic application of the brakes on the train when either of said windings has been deenergized for a given interval of time, a. normally closed contact on the train, means for opening said contact upon an automatic application of the brakes, an acknowledging switch on'the train, means on the train controlled by said acknowledging switch and by said normally closed contact for at times reenergizing either winding after such winding has become deenergized, and other means on thetrain for at other times energizing either winding after such winding has become deenergized.

5. Railway traiiic controlling apparatus comprising two normally energized traincarried windings, means on the train cooperating with devices located at intervals along the trackway for at times deenergizing one of said windings, means on the tram controlled by currents in the trackway for at s other times deenergizing the other winding,

single means controlled byboth said windings for initiating an automatic application of the brakes on the train when either of said windings has been deenergized for a given o interval of time, a normally closed contact on the train, means for opening said contact upon an automatic application of the brakes, an acknowledging switch on the train, means on the train controlled by said acknowledging switch and by said normally closed contact for at times reenergizing either winding after such winding has become deenergized, a reset switch on the train, and means controlled by said reset switch for at other times ener izing either winding after such winding has become deenerglzed.

6. Railway traffic controlling apparatus comprising two normally energized traincarried magnet valves, means on the train cooperating with devices located at intervals along the trackway for at times deenergizing one of said magnet valves, means on the train controlled by current in the track rails for at other times deenergizing the other magnet valve, means controlled by said one magnet valve for initiating an automatic application of the brakes on the train after said one magnet valve has been deenergized for a given interval of time, means controlled by said other magnet valve for giving an audible signal on the train when said other magnet valve becomes deenergized, a reset switch on the train, and means controlled by said reset switch for at times energizing either of said magnet valves after such magnet valve has become deenergized.

7. Railway trafiic controlling apparatus comprising two normally energized traincarried magnet valves, means on the train arranged for magnetic coaction with a trackof said magnet valves, means on the train controlled by currents in thestrack rails for at other times deenergizing the other magnet valve, means controlled by said one magnet valve for initiating an automatic application of the brakes on the train when said one magnet valve has been deenergized for a given interval of time, means controlled by said other magnet valve for giving an audible signal on the train when said other magnet valve becomes deenergized, a normally closed contact on the train, means for opening said contact upon an automatic application of the brakes, an acknowledging switch on the train, means controlled by said acknowledging switch for reenergizing said other magnet valve after said other magnet valve has become ClQ11Q1 lZ8Cl, and means controlled by valve, a normally closed circuit including said primary winding and the winding of said magnet valve as well as a front contact of said relay, :1 second normally closed circuit including said secondary winding and the winding of said magnet valve as well as the winding and a front contact of said relay, means controlled by said magnet valve for initiating an automatic brake application on the train after said first magnet valve has been deenergized for a given interval of time, an acknowledging switch on the train, means controlled by said acknowledging switch effective for reenergizing said first relay if and only if said switch is operated during said interval of time, a second train-carried relay, means controlled by currents in the track rails for controlling said second relay, a train-carried acknowledging relay, a pickup circuit for said acknowledging relay controlled by saidsecond relay and by said acknowledging switch, a stick circuit for said acknowledging relay controlled by said second relay, and indication means on the train controlled by said acknowledging relay and by said second relay.

9. Railway trafiic controlling apparatus comprising a train-carried receiver core arranged for magnetic coaction with a trackway inductor and provided with a primary and a secondary winding, a first train-carried relay, two train-carried magnet valves, a normally closed circuit including said primary winding and the winding of one of said magnet valvesas well as a front contact'of said first relay, a second normally closed circuit including said secondary winding andthe, winding t said one magnet valve as well as the winding and a front contact oi. said first relay, a second train -carried relay provided with neutral and reverse contacts,

a! means controlled by currents in the track rails for controlling said second relay, an acknowledging relay, a stick circuit for said acknowledging relay including its winding and its own front contact as well as a neutral contact of said second relay; a third normally closed circuit including the winding 01" the other magnet valve, a back contact of said acknowledging relay, and a normal contact oi -said second relay; single means controlled by both said magnet valves for initiating an automatic application of the brakes on the train when either of said magnet valves has been deenergized for a given interval oi time, an acknowledging switch 39, on the train, and means controlled by said acknowledging switch and effective only during said interval of time for reenergizing either said first relay or said acl mowledging relay after such relay has been dee ergized. 10. Railway traific cont-rolling apparatus comprising a train-carried magnetizable receiver core arranged for magnetic coaction with a trackwa inductor and provided with a primary and a secondary winding, a first 3L train-carried relay, two magnet valves on the train, single means controlled by both said magnet valves for initiating an automatic application of the brakes on the train when either of said magnet valves has been deenergized for a given interval of time, an acknowledging switch and a reset switch on the train, each having normally closed and normally open contacts, a source or" current on the train, a pneumatic relay provided with a normally closed contact which becomes opened upon an automatic application of the brakes; a normal circuit for said primary winding extending from one terminal of said source through a normally closed acknowledging switch contact, a normally closed reset switch contact, the winding of one of said magnet valves, a first contact of said first relay, and the primary winding to the other terminal of said source; a normal circuit for said secondary windin extending from said one terminal of said source through said normally closed acknowledging switch contact, said normally closed reset switch contact, the winding of said one magnet valve, said first contact of said first relay, a second contact of said first relay, the winding of said first relay, the secondary winding, and a portion of said primary winding to the other terminal of saidvsource; a first acknowledging circuit extending from said one terminal of the source through the normally closed con tact of said pneumatic relay, a first normally open aclmowledging switch contact, a first resistance, the winding of said one relay, said secondary winding, and the said portion of essen the, primary winding to the other terminal ofsaid source; a second acknowledging circuit extending from said one terminal of the sourcethrough'a second normally open acknowledging'switch contact, a second resist ance, and said secondary winding to the other terminal-of the source, said second acknowledgingcircuit having a branch which extends froin said. second normally open acknowledging switch contact through said second resistance, said first contact of said first relay, said second contact of said first relay, the winding of said first relay, and said secondary winding to the said portion of said primary winding; a first reset circuit which extends from said one terminal of the source through a first normally open reset switch contact, said first resistance, the winding of said first relay, the secondary winding, and the said portion of the primary winding to the other terminal of said source; said first reset circuit'having a branch which extends from said one terminal of the source through said normally closed acknowledging switch contact, a second normally open reset switch contact, said second resistance, and said primary finding to the other terminal of said source; a second train-carried relay provided with neutral and normal contacts, means on the train controlled by currents in the track rails for controlling said second relay, a stop and a proceed lamp on the train, means controlled by normal contacts of said second relay for energizing said proceed lamp, means controlled by neutral contacts of said second relay for energizing said caution lamp, an acknowledging relay on the train; a third acknowledging circuit which extends from said one terminal of said source through the normally closed contact of said pneumatic relay, a third normally open contact of said acknowledging switch, the winding of said acknowledging relay, and a neutral contact of said second relay to the other terminal of saidsource; a second reset circuit which passes from said one terminal of said source through a third normally open contact of said reset switch, the winding ofsaid acknowledging relay, and a neutral contact of said second relay to the other terminal of said source; and a stick circuit for said acknowledging relay which extends from said one terminal of said source through a neutral contact of said second relay, a front contact of said acknowledging relay, and the winding of said acknowledging relay to the other terminal of said source.

11. Railway trafiic controlling apparatus comprising two normally energized traincarried windings, means on the train cooperating with devices located at intervals along the trackway for at times deenergizing one of said windings; means on the train controlledby currents in the trackway for at other times deenergizing the other winding, a timing reservoir on the train means controlled by both of said magnet Valves for exhausting said timing reservoir to atmosphere at the expiration of a predetermined time interval after either of said magnet valves becomes deenergized, a whistle connected with said timing reservoir by means of said valves when either of said valves is deenergized, two check valves one located between said Whistle and each of said valves, and a relay valve responsive to the pressure in said timing reservoir and arranged to initiate an automatic application of the brake on the train when the pressure in said timing reservoir has decreased below a predetermined value.

In testimony whereof we aliix our signatures.

HAROLD V. RUDOLPH. HAROLD W. BRYAN. 

